Blown-In Insulation vs Batt Insulation

A roll of batt insulation.

Properly insulating your home is critical in saving energy over the long haul. Whether you need to install more insulation in the attic or need some for a remodeling project, you will typically run across two types of insulation — blown-in and batt. From different types of material to overall advantages and disadvantages, here is everything you need to know about blown-in versus batt insulation.

What Is Batt Insulation?

A man installing batting insulation in an attic.

Batt insulation comes in long rolls and is sometimes referred to as blankets. The insulation is comprised of long, interwoven fibers that are held together with adhesives. Batt insulation is rolled and cut into place and can be installed in pretty much any location of the house, including the attic and walls.

The two most common types of batt insulation are cotton and fiberglass. Some varieties will also feature a vapor barrier along the back of the roll. There is not a big difference between cotton and fiberglass in terms of insulation. Cotton batts, however, are more environmentally friendly and are made from recycled jeans.

Advantages of Batt Insulation

Batt insulation is easy to install and requires zero specialized tools to get the job done. It also offers a little better thermal resistance than its counterpart. Compared to blown-in insulation, batts can reach a resistance rating (R-factor) of over 3.1. Blown-in varieties, however, typically reach a peak of around a 2.8 R-factor. The maximum rating of batt insulation is around 4.2.

Disadvantages of Batt Insulation

The biggest disadvantage of batt insulation is that it does not fit well in non-standard spaces. The batts need to be cut to fit into small spaces, which can be tricky in poorly lit rooms and tight areas. If you cut the batt too small, then you will lose energy. You can avoid this, of course, by cutting the batt to a proper size, though this does expend more time in the installation process.

What Is Blown-In Insulation?

Blown-in insulation.

Blown-in insulation works exactly how it sounds. The insulation is literally blown into the space and covers the area without having to cut anything to size. Blown-in insulation comes in a variety of materials, including fiberglass, cellulose, and mineral wool. The cellulose variety is manufactured from recycled newspapers and actually has a better thermal rating than fiberglass.

Advantages of Blown-In

Blown-in insulation is great for spaces that are not uniform in size. In fact, you can cover large areas with blown-in insulation in very little time and do not have to worry about gaps or working around electrical wires. If time is an issue and your attic is filled with inconsistent spaces, then blown-in insulation is probably the better option.

Disadvantages of Blown-In

The biggest disadvantage of blown-in insulation is that it requires a special tool for the job. When installing this type of insulation, you will need a blowing machine equipped with a large hose. It's also difficult to ascertain the exact thermal rating of blown-in insulation because the material is often not uniform in thickness.


The overall cost of blown-in insulation versus batts depends on location, however, it's typically within a few cents per square foot. That said, the cost of blown-in typically includes the price of professional installation, which will save you a lot of time and labor over batt insulation.